1. Field of the Invention
The present invention relates to a reagent cassette used in an automatic analyzer for carrying out qualitative and quantitative analyses of a component to be measured in a biological sample. More particularly, the present invention relates to a reagent cassette of a structure in which plural types of reagent bottles are combined together into one reagent cassette.
2. Description of the Related Art
A biochemical test for analyzing a component contained in blood of a patent is generally performed through the steps of reacting a serum obtained by centrifugal separation of the blood with a reagent, and quantitatively measuring a color developed with the reaction by a photometer. In such a test, two or more types of reagents are usually employed because it is difficult to analyze the target component by using one type of reagent from the principle point of the measurement.
The number of tests and the amounts of reagents carried out and used per day greatly differ even for the same measurement item in accordance with operating situations of various facilities depending on hospital scales such as a large general hospital and a small clinic, and measurement types such as dedicated for nighttime treatment, emergent patients and daytime patients.
Reagents have such a limitation in practical use that, because a reagent for a clinical test employs biological materials, e.g., an enzyme and an antiserum, the effective period of the reagent after opening of a reagent bottle is short. The effective period is usually about one month. Even with the same item measured in tests, if the reagent bottle has a large capacity, the reagent cannot be completely used in the effective period after opening of the reagent bottle. In other words, the reagent is discarded in some cases.
Taking into account the above-described operating situations and limitation on reagents, the reagent used even for the same measurement item is marketed as two types of commodities, i.e., a large-capacity package for use in large-scale test centers and a small-capacity bottle for use in nighttime urgent tests.
Practically, reagents have hitherto been used in two kinds of methods. According to one method shown in FIG. 9, information regarding the content of a reagent bottle is specified for each reagent bottle. According to the other method shown in FIG. 10, a plurality of reagents used for one measurement item are combined together into one reagent cassette and are employed in tests for that measurement item. Then, information regarding all the reagents is specified on the cassette.
When information regarding the content of a reagent bottle is specified for each reagent bottle according to the one method, items of information, such as the reagent type (e.g., a first reagent or a second reagent), the reagent bottle code, and the number of times of feasible measurements, are incorporated in a reagent barcode. Also, analysis parameters set in an analyzer include basic analysis conditions, such as the measurement wavelength, the sample amount and the calibration method, per measurement item and the reagent bottle code per reagent type.
When, according to the other method, a plurality of reagents used for one measurement item are combined together into one reagent cassette and employed in tests for that measurement item, and information regarding all the reagents is specified on the cassette, plural types of reagent bottles used in the test for that measurement item are put on the cassette. A combination of the reagent bottles is decided beforehand and cannot be changed. In practical use, analysis parameters for each reagent cassette are given as analysis conditions set in an analyzer and selected based on a reagent cassette code serving as a key.
The structure of one reagent cassette on which a plurality of reagent bottles are put together is disclosed in, e.g., Patent Reference 1; JP,A 5-302924.